Gadgetory

SLI and crossfire I'm technologies often touch on is they don't interest me that much more importantly the evidence would suggest most gamers aren't that interested either with very few choosing to run more than one GPU though granted the pricing is likely the ultimate issue here my reasons for disliking SLI and crossfire is simple in my experience it just isn't a practical means of accessing extra performance i'm not saying either technology is bad but it should be reserved for the most extreme GPUs available at the time software support plays a major role here and quite a bit of work needs to be done by both the game developer and NVIDIA to allow their multi GPU technology to scale well sadly this doesn't always happen and gamers are often left with less than desirable performance it's not I guess lie is a new technology either in fact scalable link interface technology was first developed by 3d effects back in 1998 when it was introduced with the Voodoo 2 I might add this was before I got into PC gaming - but I was 10 years old so I feel like I can be excused apparently back then scaling was limited by CPU performance and it wasn't until later in 2004 after in-video acquired 3d effects that they introduced sli with a GeForce 6 series with a greater degree of success since then SLI hasn't changed a great deal the GeForce 8 series and they were scaling beyond just two cards and that's remained a feature right after the GeForce 9 series now the recently released GeForce 10 series saw a few changes made to SLI the most noteworthy of which is the new sli bridge which uses both sli connectors or fingers to connect just two cards this has been done to increase the available bandwidth between the two graphics cards by using both connectors the new sli interface runs a 650 megahertz and maxes 63 percent frequency bump over the old 400 megahertz bridges because both connectors are now required to efficiently connect to GeForce 10 series graphics cards this takes three-way and four-way support off the table there's been a huge amount of confusion about this topic but in short only to a sli is now officially supported and frankly I think that's a good thing full disclaimer though it is possible to link more than two GeForce 10 graphics cards together using legacy SLI bridges but other than showing how much money you can on your rig there really is a much point invidious game ready drivers will include three and four-way SLI profiles to select benchmarking applications such as fire strike Unigine and catzilla this of course will allow in videos name to remain high on the benchmarking charts as for games though we really only expect to see two-way support so then you've decided to bite the bullet and get yourself a pair of GT X 1080 graphics cards you've worked hard and you deserve it the only question now is do you shell out another 40 dollars for the high bandwidth sli bridge or do you stick with the one that came with your motherboard having spent fourteen hundred bucks on 1080 graphics cards already what's another forty bucks still it would be nice to know if that fancy looking bridge does anything more than just look well fancy that's what I plan to find out today as I stick a pair of GD X 1080 and gtx 980ti graphics cards together using the new sli bridge and comparing it to the old single connector flex bridge i got for free with a zeb 170 motherboard okay so for testing my standard GPU testing machine has been used and the latest game ready drivers were used to test both the gtx 980ti and GT X 1080 configurations I'll be focusing on 4k performance as this high resolution should push the bandwidth across that sli bridge the results are extremely interesting surprising and perhaps even a bit confusing but before we get to that let's start with what I was expecting to see first up we have ARMA 3 a game that plays well below 60fps on a single 1080 when using the high-end game quality settings adding a second 1080 boost performance by an impressive 74% with the old flex bridge using that new high bandwidth bridge pushes that figure up to 79% though I should point out it was just 2 fps this is pretty much of the margin of error for testing even with a three run average honestly this is more or less the kind of performance I was expecting to find here we have another super demanding game in Crysis 3 and while adding a second 1080 allow for a 71 percent performance boost using the high bandwidth bridge didn't improve that figure dirt rally only sees a 65 percent performance boost when enabling SLI and the GD X 1080 cards of 4k but to be fair that sees even the minimum frame rate stay about 100 FPS using the high bandwidth bridge has no impact on performance to you the 980ti sli cards provides 69% more performance in Star Wars Battlefront meanwhile GD a DSLR scout even better of providing 88% more performance using the Flex bridge the high bandwidth bridge allows almost perfect scaling at 96% which was impressive to see if I was ever gonna see a reasonable game using the new high bandwidth bridge I expected to see in Far Cry primal as it turns out SLI scaling for the 1080 s is pretty good here we see a 76% performance boost while the high bandwidth bridge isn't able to improve performance further rise of the Tomb Raider was another game that I thought might show a real benefit from having more SLI bandwidth despite only seeing a 66% increase in performance when adding a second GD X 1080 the high bandwidth bridge only increased that margin by 5% for an extra three fps better than nothing I guess here we see yes the light scales superbly well in college ad black ops 3 as we go from an average of 58 FPS for the single GTX 1080 to 104 fps using the Flex bridge this is the nice 79% improvement despite that great result we see the high bandwidth bridge is able to improve performance even further resulting in a 91% performance gain over the single card configuration this is great stuff and more than what I was hoping to find okay so this is where things get interesting using the Flex bridge the GTX 1080s provides us 23% more performance over a single card so pretty abysmal scaling this is pretty much what we've come to expect in Witcher 3 though using these quality setting as the 980ti sli cards with just 35% faster than their single card configuration using the high bandwidth bridge does nothing to help the gtx 980ti graphics cards but it works wonders for the 1080s here we see a massive 26 percent performance gain over the Flex bridge for an average of 67 FPS 56 percent more performance in a single 1080 still far from the best scaling was seen but a massive improvement over using a legacy sli bridge connector if you lower the quality settings to say medium sli scaling picks up considerably in the witcher 3 with the Flex connector so this does indeed suggest that the poor scaling it is a result of limited bandwidth between the cards Tom Clancy's the division has more interesting results for us here we see a huge 33 percent performance game when using the high bandwidth her sly bridge over the Flex bridge here the Flex bridge allowed the SLI 1080s to deliver just 13% more performance while the high bandwidth bridge allows for a 51 percent performance boost again not the best SLA scaling you get a set but a vast improvement nonetheless with the high bandwidth bridge CPU utilization increased by over 30 percent with a flex bridge we sought a 60% utilization on the GPUs while near 100 percent usage was seen with the high bandwidth bridge something worth noting here is that the high bandwidth bridge also boosted the performance of the gtx 980ti graphics cards providing an 11 percent performance boost granted that isn't nearly as significant as what was seen with the 1080 graphics cards but to my knowledge the high bandwidth bridge isn't meant to help the Maxwell GPUs in SLI one game that constantly throws up unusual results is fallout 4 in keeping with tradition it has the most extreme legacy versus high bandwidth SLI bridge results yet fallout 4 is a bandwidth Pig but a 42% performance game when going from the legacy to the high bandwidth bridge is massive this means while I slide only scaled by 20% previously it's now showing a 71 percent performance improvement with the high bandwidth bridge over a single 1080 card configuration unfortunately the high bandwidth bridge doesn't help the Maxwell base gtx 980ti graphics cards ok so the mission here was to try and determine if there's a tangible difference between the legacy bridge that you probably got for free with your motherboard an expensive 40 US dollar higher bandwidth bridges that have video claims you now need also while I do plan to run the SLI 1080s and eventually ten 70s through my 20 plus game gauntlet that wasn't required for this video instead the 10 game sample will painted a rather interesting picture of course of the ten games tested the high bandwidth bridge only showed noteworthy gains and just Raven that said we essentially went from a situation where SLI was almost broken to one where it was scaly and over 50 percent that extra performance was very welcome to 4k I have to admit I was a bit hesitant to publish these results at first I wasn't convinced there wasn't something unforeseen influencing the results but after countless back and forth between the Flex bridge and the high bandwidth bridge the results were confirmed reconfirmed reconfirmed again and a few more times before I accepted what the test system was giving me with nothing else being changed here the performance difference had to be coming from the sli bridge some users have been reporting performance gains when using two single bridges for their 1080 sli setup to my knowledge this caused issues with the maximal base cards but I decided to give it a shot after completing all the testing previously to my surprise with the two flex connectors installed I received the exact same performance boost in The Witcher 3 division and fallout 4 as I did with the high bandwidth bridge so it seems if you have two legacy connectors you don't actually need a high bandwidth bridge surprisingly despite others running GD X 1080 SLI tests no one else seems to have compared the high bandwidth bridge with the legacy bridge if someone can confirm or contradict my results please drop a comment below thanks for joining me again our Hardware unboxed I'm your host Matt as always and I'll see you guys next time youtubers like me depend on your support to continue improving the quality and content of our videos to support the channel directly consider becoming a patron to also get access to a heap of cool rewards and exclusive giveaways also don't forget you can check prices and buy the products I looked at in this video through the Amazon links in the video description below thank you kindly for supporting me and the hardware on box channel it means a lot to me and I really do appreciate it and in return I'll continue to work as hard as I can to keep producing the content you enjoy